Electric relay combination with latching interlocking means



March 29, 1966 G. A. JELLEY ELECTRIC RELAY COMBINATION WITH LATCHING INTERLOCKING MEANS Original Filed March a, 1961 2 Sheets-Sheet l v Ettorrfty March 29, 1966 G. A. JELLEY ELECTRIC RELAY COMBINATION .WITH LATCHING INTERLOCKING MEANS I Original Filed March 6, 1961 Attorney Un ted St t s P tent ELECTRIC RELAY C(iMBlNATION WITH LATCH- ]NG INTERLOCKING MEANS Gordon Albert Jelley, Walsall, England, assignor to J. A.

Crabtree & Co. Limited, Walsall, England, a British This is a division of application Serial No. 93,518, filed on March 6, 1961. i

This invention relates to multipole electric relays of the kind in which an armature is adapted to be displaced under the control of an electromagnet to actuate a carrier having moving contacts which are engageable with fixed contacts.

One object of the present invention is to provide a relay with a mechanical hold-on device which is releasable by a second relay to prevent undesirable re-opening of the normally open contacts until a sequence of operations is terminated by the operation of the second relay.

In accordance with the invention an electric relay arrangement comprises a pivoted latching member adapted for holding the contacts of one relay closed by means of a slot therein into which a pin, projecting from a contact carrier of said relay extends, said pin being releasable by a companion relay adapted, when operated, to turn the pivoted member to release the pin so that the contact carrier may re-open the said contacts of the first mentioned relay.

Thus the invention contemplates a latching mechanism for electric relays in which one relay can close and latch its-elf to remain closed, even though the current through its coil is cut olt, until tripped by energization of the other relay. Such arrangement is particularly adapted for interlocking auxiliary circuits useful in many industrial applications. For example, it is imperative with pumps and engines to ensure that lubrication be started before, and maintained during, running operations. Thus the first relay not only commences the lubrication before the engine starts, but also ensures continuance of lubrication during operation of the pump, etc. The latching device makes certain also that lubrication is stopped only when the companion relay is operated for stopping the pump.

In order that the invention may be more readily understood and carried into practice, reference will now be made to the accompanying drawings wherein:

FIGURE 1 is a partly exploded view of a mounting plate and one of the pair of relays mounted thereon.

FIGURES 2, 3 and 4 are respectively a plan, a side elevation, and a front elevation, showing two companion relays mounted side-by-side and provided respectively with co-acting hold-on devices, one of the relays being indicated in chain-dot lines in FIGURE 4.

FIGURES 5, 6 and 7 are diagrammatic elevations of the co-acting hold-on devices, showing the devices in three different relative positions.

Referring to the drawings, two relays A and B described in my above stated copending application, are mounted upon a channelled back plate 8. A mechanical device is provided for holding the contacts of the relay A in their operated position after the corresponding .contact carrier and armature assembly has completed its electromagnet controlled movement and the corresponding ooil has been de-energized, and until the coil of the relay B is energised to initiate the electromagnet controlled movement of the contact carrier and armature assembly of the latter relay. The relay B may therefore be regarded as a master relay and the relay A as a slave or servant relay.

3,243,547 Patented Mar. 29, 1966 The said device comprises two U-shaped stirrups or straps 46, 47,- the strap 46 being applied to the slave relay A and the strap 47 being applied to the master relay B. The base 48 of each strap passes through the clearance 49 between the substantially flat attachment plate 4 of the corresponding relay and the floor 9 of the channelin the back plate 8, transversely of the base 1 of the said relay, whereas its sides 50 embrace the relay base. As described and shown in the aforesaid application a pivot pin 51 passing through and projecting beyond the opposite ends of registering transverse grooves in the underside of the relay base and the attachment plate respectively, engages a pair of concentric holes pierced in the sides 50 in the vicinity of the base 48 of the strap. A hold-on :pin 55 extending through a transverse passage in the contact carrier 28 and through slots in the side walls of the arc chamber, engages registering slots formed in the strap sides in the vicinity of the free end-s of the latter. The slots in the sides of the straps 46 are L-shaped, one limb 58 of each slot extending longitudinally and the other limb 59 extending transversely, whereas the slots 60 in the sides of the strap 47 are inclined to the lengths of the said sides.

The strap 46 is biased by a blade spring 61 which tends to turn the strap about the corresponding pivot pin 51 in the direction which moves the transverse limbs 59 of the L-shaped slots into engagement with the corresponding hold-on pin 55. Hence, when the contact carrier and armature assembly of the slave relay completes its electromagnet controlled movement to close its normally-open contacts, the hold-on pin 55 is located at the level of the said limbs 59 and the strap 46 is turned by the blade spring 61 about its pivot pin 51 so that the said limbs engage the hold-on pin 55 (FIG. 5) and the said assembly is locked and prevented from making its spring loaded plunger return movement even the said slots and turns the strap 47 in the direction which causes the ear 62 to turn the strap 46 of the slave relay against the action of the blade spring 61, thereby moving the slot limbs 59 out of engagement with the hold-on pin 55. The hold-on pin is then located in the elbows of the L-shaped slots as shown in FIG. 6 and, as a consequence, the contact carrier and armature assembly of the slave relay is released and free to make its spring loaded plunger return movement since the hold-on pin is able to travel up the longitudinal limbs 58 of the said slots, as shown in FIG. 7.

If desired, by providing a channelled base plate 8 of sufiicient length, and by providing an outwardly projecting car on each side of the strap 47, two slave relays may be mounted on said plate, one on each side of the master relay so that the contact carrier and armature assemblies of both slave relays may be locked to hold-on their respective normally open contacts until the master relay is operated by energising its coil.

The forms of the invention here described and illustrated are presented merely as examples of how the Having thus described my invention, I claim:

- 1. In an electric relay combination, an electric relay having fixed contacts, a contact carrier and normally open movable contacts mounted on said carrier, a mechanical device "for holding said movable contacts in engagement with said fixed contacts, said device comprising a first pivoted member provided With a slot there- 'in and mounted on said relay, a pin projecting from said carrier and extending through said slot, said pin latch in'g said carrier in closed contact position when said relay is operated; .a companion relay, and a second pivoted member engaging said first pivoted member, said second member disposed on said companion relay and activated thereby 'to turn said first member, release said pin and re-open said contacts.

2. In an electric relay combination, an electric relay comprising normally open fixed and movable contacts, a carrier for said movable contacts, a first means for holding said movable contacts in engagement with said fixed contacts, said first means comprising a holding pin projecting from said carrier to latch it in closed contact position when said relay is operated, a first U- shaped pivoted member embracing said relay and provided with a slot therein, said pin projecting through said slot; a companion relay and a second means, said second means comprising a second U-shaped pivoted member disposed in side-by-side relationship with and engaging said first pivoted member, said second pivoted member embracing said companion relay and activated thereby to turn said first pivoted member to release said pin and said-carrier for actuation to re-o-pen said contacts.

3. In an electric relay combination, an electric relay com-prising normally open fixed and movable contacts, a carrier for said movable contacts, a first means for holding said movable contacts inenga'gement with said fixed contacts, said means comprising a first holding pin, a first pivoted member provided with two parallel arms, a slot disposed in each of said arms, said slots being L-shaped having two right angled limbs, said pin projecting from said carrier through said slots, wherein said holding pin is mounted on said carrier for selective engagement with'one of said limbs in each 'of said slots; a companion relay, and a second means engaging said pivoted member, said second means disposed on said companion relay and activated thereby to turn sa-id pivoted member and position said carrier for actuati'o to re-open said contacts.

4. In an electric relay combination according to claim I loaded spring, a first of said limbs is disposed substantially transverse to the line of travel of said carrier, and said loaded spring tends to turn said first pivoted mem her to engage said pin in said first limb.

5. In an electric relay combination according to claim 4 having a second contact carrier and a second' pivoted member, said second carrier and said second pivoted member being disposed on said companion relay, a second holding pin projecting from said second carrier, a second slot being inclined relative to the direction of travel of said second carrier and engaged by said second .pin, an ear projecting from said second pivoted member into the path of travel of said first pivoted member, said ear engaging and turning said first pivoted member to position said first pin in a second of said limbs when said companion relay is operated.

6. In an electric relay combination, an electric relay comprising normally open fixed and movable contacts, a first carrier for said movable contacts, a first means for holding said movable contacts in engagement with said fixed contacts, said first means comprising a first pivoted member provided with a first slot therein, a first holding pin projecting from said first carrier through said first slot; "a companion relay provided with a second contact carrier and a second pivoted member, a second holding pin projecting from said second carrier, a second slot engaged by said second pin, said second slot being inclined relative to the direction of travel of said second carrier, an ear disposed on said second pivoted member, said ear projecting into the path of travel of said first pivoted member to engage and turn said first pivoted member relative to said first pm when said companion relay is operated. 7. In an electric relay combination according to claim 6 wherein each of said relays have a body portion and a pivot pin extending through each of said body portions said first and second pivoted members each comprising a vU-shaped strap having a base and two side arms, said pivot pins extending through said arms adjacent the base thereof, and said straps extending below and embracing the sides of said body portion of each said relay when pivotally mounted thereon.

References Cited by the Examiner UNITED STATES PATENTS -2,756,6l2 7/1956 Schleicher 200-98 X 2,881,284 4/1959 Mekelburg 200-98 BERNARD A. 'GILHEANY, Primary Examiner. T. -D.-MACBLAIN., Assistant Examiner. 

1. IN AN ELECTRIC RELAY COMBINATION, AN ELECTRIC RELAY HAVING FIXED CONTACTS, A CONTACT CARRIER AND NORMALLY OPEN MOVABLE CONTACTS MOUNTED ON SAID CARRIER, A MECHANICAL DEVICE FOR HOLDING SAID MOVABLE CONTACTS IN ENGAGEMENT WITH SAID FIXED CONTACTS, SAID DEVICE COMPRISING A FIRST PIVOTED MEMBER PROVIDED WITH A SLOT THEREIN AND MOUNTED ON SAID RELAY, A PIN PROJECTING FROM SAID CARRIER AND EXTENDING THROUGH SAID SLOT, SAID PIN LATCHING SAID CARRIER IN CLOSED CONTACT POSITION WHEN SAID RELAY IS OPERATED; A COMPANION RELAY, AND A SECOND PIVOTED MEMBER ENGAGING SAID FIRST PIVOTED MEMBER, SAID SECOND MEMBER DISPOSED ON SAID COMPANION RELAY AND ACTIVATED THEREBY TO TURN SAID FIRST MEMBER, RELEASE SAID PIN AND RE-OPEN SAID CONTACTS. 